sly

1 clever at attaining one's ends by indirect and often deceptive means the movie pairs a sly, dissembling ex-con with an upstanding, straight-arrow cop Synonyms beguiling, cagey (also cagy), crafty, cunning, cute, designing, devious, dodgy [chiefly British], foxy, guileful, scheming, shrewd, slick, artful, subtle, tricky, wilyRelated Words astute, facile, glib, sharp; crooked, deceitful, deceptive, dishonest, fraudulent, insinuating, knavish, Machiavellian, oblique, serpentine, shady, shifty, slippery, sneaky, treacherous, underhand, underhanded, unscrupulous; backhanded, double-dealing, hypocritical, insincere, left-handed, mealy, mealymouthed, smooth-tongued, two-faced; circuitous, circular, roundabout; clandestine, concealed, covert, furtive, hugger-mugger, secret, stealthy, surreptitious, undercover; calculating, plottingNear Antonyms obvious, open, patent, plain, public, unconcealed; aboveboard, candid, direct, forthright, frank, honest, natural, outspoken, plainspoken, real, simple, sincere, straightforward, unaffected, unpretending, unpretentious, unvarnished; childlike, impressionable, simpleminded, unsophisticated, unworldly; unforced, unstudied; trustful, trustingAntonyms artless, guileless, ingenuous, innocent, undesigning

2 given to acting in secret and to concealing one's intentions why, you sly fellow! I had no idea you were planning my birthday party Synonyms furtive, shady, shifty, slippery, sneaky, sneaking, stealthyRelated Words artful, crafty, cunning, devious, foxy, guileful, slick, wily; close, closemouthed, reticent, secretive; clandestine, covert, dark; deceitful, deceiving, deceptive, devious, duplicitous, trickish, tricky, underhand, underhanded; cheating, crooked, defrauding, dishonest, dissembling, double-dealing, knavish, two-faced; lying, mendacious, untrustworthy, untruthful; insidious, perfidious, serpentine, treacherousNear Antonyms aboveboard, forthright, plainspoken, straightforward; candid, direct, foursquare, frank, open, plain; honest, trustworthy, truthful

3 tending to or exhibiting reckless playfulness a sly sense of humor Synonyms arch, devilish, elvish, espiègle, impish, knavish, leprechaunish, pixie (also pixy), pixieish, prankish, puckish, rascally, roguish, scampish, mischievous, tricksy, waggish, wickedRelated Words antic, coltish, coy, frisky, frolicsome, kittenish, playful, sportful, sportive; gay, happy, lighthearted, whimsical; energetic, lively, spirited, sprightly; artful, crafty, cunning, trickish, tricky, wily; misbehaving, naughty, troublemaking; pestering, riling, teasingNear Antonyms grave, grim, sedate, sober, solemn, staid, stern